I would like to ask what the meaning is behind the naming rules for the propane-based refrigerants HC-290 and R290

HCFC: Hydrogen-containing chlorofluorocarbon is an abbreviation for hydrochlorofluorocarbons; it includes refrigerants such as R22, R123, R141b, and R142b. Their ozone-depletion potential is only a few percent of that of R11. Therefore, China’s Plan for the Phased Outplacement of Ozone-Depleting Substances regards HCFCs as the most important transitional alternatives to CFCs. HFC: Hydrofluorocarbons is an abbreviation for hydrofluorocarbon compounds; it includes refrigerants such as R134a, R125, R32, R407C, R410A, and R152. Their ozone-depletion potential is 0, but their global warming potential is relatively high. Another category is CFCs, or Chlorofluorocarbons – a shorthand for these chlorofluorinated hydrocarbons. They include refrigerants such as R11, R12, R113, R114, R115, R500, and R502. Due to their significant impact on the ozone layer, they have been listed as controlled substances under the Montreal Protocol. The use of such substances has been gradually banned in our country. PFC, Perfluorocarbon, refers to fully fluorinated hydrocarbons. To distinguish the degree of damage caused by these substances to the atmospheric ozone layer, R is often replaced by CFC, HCFC, HFC, and HC respectively. CFC – Chlorofluorocarbons, contain chlorine but no hydrogen; they are pollutants that severely damage the ozone layer and have been banned. HCFC – Hydrochlorofluorocarbons, contain both chlorine and hydrogen; they pose less of a pollution risk and are considered transitional substances. HFC – Hydrofluorocarbons, do not contain chlorine; they cause no pollution and can be used as substitutes. HC – Hydrocarbons, contain neither chlorine nor fluorine; they cause no pollution and can also be used as substitutes